Homework SourseWhich variable changes most frequently to affect cardiac out
Solution
Answer:
[All the answer has been covered with precise and understandable manner]
There are several factors/variables are there, which directly or indirectly affecting cardiac output. Catecholamines, the chemicals produced during periods of excitement such as activity, exercise or work, can cause an increase in both heart rate and stroke volume thereby greatly increasing cardiac output. Medications or poisons that slow the heart rate or decrease the heart\'s ability to forcibly contract will often decrease the cardiac output, often to critically low levels. During a myocardial infarction, or heart attack, there can be significant variations in cardiac output. Often in the beginning phase of a heart attack the body responds by increasing catecholamine production, which can increase cardiac output. This can cause increased pressures against which the heart has to pump, further increasing the workload of a heart that is already experiencing muscle tissue death due to the blockage of an artery. During or even after a heart attack, the muscle tissue that is damaged can have devastating effects on the heart\'s ability to pump. Often the results can be significantly reduced left ventricle contraction and subsequently heart failure. Once the heart begins to fail, fluid can back up into the lungs leading to congestion or wet lung sounds. This is often referred to as congestive heart failure. Chronic high blood pressure, smoking, drug use, kidney disease, high cholesterol, lack of exercise, poor diet and other genetic and lifestyle factors can affect the heart\'s ability to contract and pump blood.
